Sometimes we also call cavity filled ball valve a full-capsulated ball valve or Non-retention Ball Valve, as we know, the ball valve inside has a ball to control liquid flowing through it. The normal ball valve gasket seal is half-capsulated the ball, normal ball valves usually have a small gap between the ball and the seal, and there will be a slight residue after the medium flows through.
The difference is the below PTFE full covers the ball or half covers the ball.
The full-capsulated ball valve with non-retention does not have cavities that can trap media that bacteria can feed on and multiply.
suit for higher working temperature and long term high-temperature work.